High purity fused silica glass is typically made by a flame hydrolysis process, which may be a soot-to-glass process or a direct-to-glass process. Examples of soot-to-glass processes include chemical vapor deposition (CVD) processes such as outside vapor deposition (OVD), inside vapor deposition (IVD), and vapor axial deposition (VAD). Glass preforms made from CVD processes are typically in the form of a cylinder having a length-to-diameter ratio much greater than 1. These cylindrical glass preforms typically require reshaping into a plate or other flat configuration before further processing into optical elements such as lenses. Further, these cylindrical preforms tend to exhibit concentric, circular micro-striae due to variations in composition, e.g., β-OH concentration, and/or physical properties, e.g., refractive index, within the bulk of the glass.